The present invention relates to the building industry and specifically to mounting equipment and the method for securing this equipment to rafters. The mounting equipment, once secured to the rafters, can be used to support objects such as solar panels.
The roofs of building structures have been used for placement of many objects such as air conditioning units, solar panels, satellite dishes, etc. The primary reason for location of these objects upon a roof is the lack of alternative space.
Air conditioning units, because of their relative heavy weight, provide a downward force upon the roof in any weather condition. However, a problem exists for other objects such as satellite dishes and solar panels, which can, in certain windy conditions, be lifted off the roof mounting because the force of the wind applied against the surface area on the side or underside of the object creates an uplift condition which is greater than the attachment strength of the roof mount to the roof deck.
Besides the need for compliance with governmental building code requirements, a more efficient method for installing a mounting system to a roof is highly desired by roof installers. A faster installation would reduce the labor costs associated with each install.
One of the problems with present installations is the fact that more than one lag bolt or other type of fastening bolt is required for each mounting plate which is secured to the roof. The risk is high that some of the lag bolts will drill at an angle other than perpendicular to the roof rafter. The severity of the angle and the trajectory of the lag bolt penetration into the rafter could cause the rafter to split; further reducing the structural integrity of the mounting system.
For many years, existing solar mounting systems were installed using a threaded pipe nipple that screwed into a mounting plate commonly called a xe2x80x9cfloor flangexe2x80x9d in the trade. The threaded floor flange has been commercially available as a standard plumbing item for many years. U.S. Pat. No. 5,603,187 issued to Merrin et al. is typical of the prior art. The Merrin design, as well as all similar prior art, have a common design limitation. They all require that multiple bolts be installed offset from the threaded vertical support flange or stanchion. Also, because of the floor flange design, it would not permit industry standard flashing to install flat on the roof; primarily due to the base flashing circumference interfering with the height of the floor flange.
A mounting system based upon the Merrin patent, while appropriate for roof mounting of heavy objects such as air conditioners, is not practical for use with solar panels or satellite dishes. The Merrin design precludes direct (bolted) attachment to the roof rafter by each of the mounting holes present on the base plate; primarily due to the width of the rafter in relation to the spacing of the mounting holes. Further, Merrin views rafter attachment as a limitation and therefore teaches away from using rafters for structural support. Therefore, Merrin teaches attachment to the roof decking which generally consists of only plywood or a composite sheeting; either of which do not provide the strength of a bolt mounted to a rafter in an uplift condition.
This invention presents a new mounting system for elevating and supporting objects such as solar panels and satellite dishes upon a roof. The roof mount would be attached prior to installation of the roof flashing. The component parts for supporting a solar panel or satellite dish would be assembled and attached to the roof mount over the flashing. Features of the invention are as follows:
1. a new roof mount having a threadable elongated member or stanchion which requires a single lag bolt positioned directly beneath the stanchion for fastening to a roof rafter. A guide tunnel is also provided on the roof mount for proper drill angle into the rafter.
2. A support design comprising either a composite or aluminum extruded C-shaped horizontal members and associated equipment for attachment to a plurality of roof mounts which will support a mounted object such as a solar panel. The design, when utilized and having upon it mounted a solar panel or other structure, enhances the strength properties from that of a C-shaped horizontal member to those of a square structural member.
3. The support design permits efficient packaging, resulting in minimal packaging time and cost.
Roof Mount
In order to utilize my mounting system, a roof mount must first be secured to a rafter. The roof mount is preferably machined from aluminum and comprises a threaded cavity with an insertion opening for threadably receiving a vertical stanchion. Directly below the cavity is an aperture for insertion of a lag bolt for attachment to the rafter. This is a unique feature of my support base. Only one lag bolt or other type of fastening bolt is required. For a one bolt design, having the attachment force positioned directly beneath the stanchion provides the highest level of attachment strength.
Additionally, a special hollow can be machined at the base of the channel to allow clearance for the bolt head when installed so that it does not contact the bottom surface area of the stanchion. This permits maximum threadable engagement of the stanchion to the base.
The base section of the roof mount comprises a base for direct contact with the decking surface of a roof and a vertically extending cylindrical member having the threaded cavity and an offset wall having a guide tunnel. It is not necessary that the guide tunnel be part of the cylindrical member. It is however, preferable to maintain a minimum distance between channel and guide tunnel so that it is easy to use the guide tunnel to drill a pilot hole into a rafter and to thereafter align the pilot hole with the aperture by sliding the base section a minimal distance.
The distance between the cavity and guide tunnel however, must be sufficient so as not to compromise the overall structural integrity of the base section.
In an alternative design, the guide tunnel is not used and the roof mount base section simply incorporates my single bolt design described above which includes a base and a vertically extending cylindrical member having the threaded cavity.
The base can be of any geometrical shape such as circular, rectangle or square. All that is required is that the geometrical shape be sized accordingly so that it does not interfere with the alignment or use of commercially available flashing to the roof.
Once the lag bolt is secured to the rafter, one end of the stanchion is inserted and secured within the threaded cavity and the roof flashing is thereafter installed. For purposes of this specification, the base section and the stanchion/elongated member are collectively referred to as the roof mount. Although the mounting equipment may be installed days later, it is preferable to install the roof mount at this point.
Solar Panel Support and Installation
A pair of C-shaped horizontal members are provided for attachment to roof mounts and support an object, such as a solar panel, above the roof. Each horizontal member is preferably made from extruded aluminum and can be manufactured to any length. Each horizontal member has a track which can be used by slidable inserts which have been designed to fit within and slide along this track. These slidable inserts have a female threaded hole for receiving a fastening bolt; the use of which will be described later.
A clamp having a hole is provided for each slidable insert. The clamp hole is positioned so that a fastening bolt can be inserted through and secured to the threaded hole of the threadable insert. There are two types of clamps available: end clamps and bi-module clamps.
Bi-module clamps are primarily used for securement of the sides of two solar panel modules. A module is a set of photovoltaic cells while a solar panel is a plurality of modules. End clamps would secure the sides of a solar panel. In any case, bi-module clamps are used to secure the sides of two adjoining solar modules to the horizontal member.
Each horizontal member has a pair of end clamps for securement of a solar panel. Each end clamp has a slight rise or heel on its bottom surface distally positioned from its clamping surface. This slight rise provides a pair of advantages when attaching solar modules. First, the slight rise prevents twisting of the clamp while it is being bolted into position on the horizontal member. Second, when the end clamp is engaged to a solar module frame, the rise forces the clamp inward at 90 degrees to fully engage a module frame. This design prevents the end clamp from inadvertently separating the module frame from its glass. Also, the rise provides spring tension against the module frame, providing full engagement as the module laminate glass and frame flex under extreme stresses caused by weather conditions such as high wind and snow.
The solar panel support includes the horizontal members, slidable inserts, end clamps, bi-module clamps and the attachment means to a roof mount. The roof mount can be the one described as part of this invention or it can be one already available in the prior art. The attachment means would comprise holes drilled in the horizontal members which are aligned with and mounted to the already installed roof mounts. A mounting bolt or the like would be used to attach the horizontal members to the roof mount.
Alternatively, it is possible to use composite material instead of aluminum for the solar panel support and roof mount.
Packaging
The horizontal members and associated mounting equipment described in the preceding section have been designed so that they can be packaged quickly; resulting in minimal labor cost associated with packaging as well as reduced packing material cost. The design prevents damage to the mounting equipment by effectively enclosing the clamps and inserts between the C-shaped horizontal members. With the open side of the C-shaped horizontal members facing each other, an elongated tubular square member is formed and all that is necessary from a packaging standpoint, is sealing the ends of the tubular member. Horizontal ridges are formed into the end surface of the open sides. The engagement of these ridges from facing C-shaped horizontal members mate or interlock. This maintains the elongated tubular configuration and facilitates product packaging.